In this section, we highlight the key high-impact studies, updates, and analyses published in medicine during the past week.
A Randomized, Controlled Trial of an Aerosolized Vaccine against Measles
While an effective injected measles vaccine has been available since 1963, world-wide goals to eliminate measles seek to develop low cost, less invasive vaccination approaches that can administered in areas with little healthcare infrastructure by people with limited clinical training. In this international trial of 2004 infants between 9 and 12 months of age at eight health centers in India, participants were randomized 1:1 to injected subcutaneous vs. aerosolized vaccine for measles. At 91 days after administration, a lower proportion of infants who received aerosolized vaccination were seropositive (85.4% vs. 94.6%, difference of -9.2%, 95% CI -12.2 to -6.3). There were similar numbers of adverse events with no serious adverse events reported in either group. While the aerosolized was effective, it was less effective than the subcutaneous vaccine and inferior by the prespecified margin.
Recurrent or metastatic squamous cell carcinoma of the head and neck have poor prognosis and there is limited evidence of comparative efficacy for various second-line chemotherapy options. In this international, multicenter, randomized controlled trial, 483 adult patients with recurrent or metastatic squamous cell carcinoma of the head and neck with good performance status were randomized 2:1 to afatinib or methotrexate. There was a statistically significant increase in progression free survival with afatinib over methotrexate (2.6 months vs. 1.7 months, HR 0.80, p = 0.03). With afatinib, there was statistically significantly more rash, diarrhea, and fatigue. Overall, serious adverse events occurred in 14% of patients treated with afatinib vs. 11% of patients treated with methotrexate. EGFR mutation tyrosine kinase inhibitors could have a role in the treatment of advanced squamous cell carcinoma of the head and neck.
Mechanical and bioprosthetic valves are both used for mitral valve replacement with significant advantages and disadvantages with each type of valve. There have been no direct clinical trial data comparing the efficacy and survival of the types of replacement valves. In this retrospective cohort analysis, investigators used a dataset of 3433 patients between 50 and 69 years of age who underwent isolated mitral valve replacement in New York State hospitals between 1997 and 2007. In this analysis, there was no statistically significant difference in mortality after matching by propensity score (15-year survival 57.5% after mechanical valve vs. 59.9% after bioprosthetic valve, p = 0.62). The rate of strokes replacement (14.0% vs. 6.8%, HR 1.62) and bleeding events (14.9% vs. 9.0%) was higher after mechanical valve, however the incidence of reoperation was lower (5.0% vs. 11.1% with bioprosthetic). There are unique advantages and disadvantages to both mechanical and bioprosthetic valves for mitral valve replacement with no significant survival difference at 15 years.
Therapeutic hypothermia is used for neuroprotection and decreasing cognitive impairment after cardiac arrest. Recent studies have queried the optimal temperature goal for therapeutic hypothermia. In this prospective international randomized controlled trial, 652 patients who survived out of hospital cardiac arrest were randomized to therapeutic heparin to a goal of either 33 or 36 degrees Celsius. There were similar rates of survival to 180 days (54% at 33 degrees vs. 51% at 36 degrees. About 50% of patients in both groups had mild cognitive impairment by the Rivermead Behavioural Memory Test. The authors found similar levels of cognitive in patients who had an ST elevation myocardial infarction without cardiac arrest, and suggest chronic comorbidities contribute to mild cognitive impairment and might not be directly related ischemic brain injury during cardiac arrest.
Association of Maternal Diabetes With Autism in Offspring
There has been no described relationship between maternal diabetes and autism spectrum disorders in offspring. In this retrospective cohort study, investigators examined the records of 322,323 singleton births born between 1995-2009 at a large regional integrated healthcare system in Southern California, the presence of pre-existing maternal diabetes or gestational diabetes and the diagnosis of autism spectrum disorders. On review, investigators found 3388 children diagnosed with autism spectrum disorders, with unadjusted incidences of 3.26, 3.02, 1.77, and 1.77 per 1000 births of mothers with preexisting type 2 diabetes, gestational diabetes before 26 weeks, gestational diabetes after 26 weeks, and no diabetes respectively. After adjustment with many covariates including maternal age, education, income, and ethnicity, preexisting maternal diabetes was not associated with autism spectrum disorders (HR 1.21, 95% CI, 0.97-1.52), however there was a relationship with gestational diabetes diagnosed before 26 weeks (HR 1.42, 95% CI: 1.15-1.74). While there was no relationship with preexisting maternal diabetes or gestational diabetes diagnosed after 26 weeks, this study suggests there is a relationship between gestational diabetes diagnosed before 26 weeks and autism spectrum disorders in offspring.
Image: PD
©2015 2 Minute Medicine, Inc. All rights reserved. No works may be reproduced without expressed written consent from 2 Minute Medicine, Inc. Inquire about licensing here. No article should be construed as medical advice and is not intended as such by the authors or by 2 Minute Medicine, Inc.